Centralized traffic controlling system



March 19, 1935. F w. BR|XNER CENTRALIZED TRAFFIC CONTROLLNG SYSTEMS Filed May 25, 1952 5 pm ENE 2 8 3:0 wuwuuzzo rlllll. |..lllL .5 30 B t @MOQEW myt s 5 Patented Mar. 19, 1935 UNITED STATES CENTRALIZED TRAFFIC SYSTEM CON TROLLING Frederick W. Brixner, Rochester, N. Y., assignor to Genera ester, N. Y.

Railway Signal Company, Roch- Application May 25 1932, Serial No. 613,483 3 Claims. (014177-353) This invention trol systems for I and more particularly pertains to the communication part of such systems.

In a centralized traffic control system relates to centralized traffic conbetween successive series. In accordance with of an impulse or between two successive impulses Other features of the present invention reside in the various specific circuit arrangements particularly adaptable for systems of this type; j

These characteristic features of the invention thus briefiy stated, will be explained more in detail in the following description of one embodiment of the invention; and various other characteristic features, functions and advantages of a system embodying this invention will be in part pointed out and in part apparent as the description progresses.

In describing the invention in detail, reference able reference characters, and in whichz- The accompanying drawing illustrates-in a diagrammatic manner the apparatus and circuits 'these'symbols are used,

having been made construction and arrangement of partsthat would be employed in practice; Thus, the various relays and their contacts are illustrated in a conventional manner, andsymbols are used toindicate the connections to the terminals ofbatteries or other suitable sources of electric current instead of showing all these terminals.

The symbols and are employed to indicate the positive and negative terminals respectively of suitable batteries; or other sources of direct current; and the] circuits with which these symbols are used, always have current flow ing in the same direction. The symbols (3+) and (B) indicate connections to the opposite terminals of suitable batteries, or other designated 1 (CN) the particular terminal used in combination'with the intermediate tap (CN). Communication .system generalZy.A, centralized traffic control system in which the pres ent invention is more particularly useful, consists ofa control office and a large number'of outlying field stations. Communication is established between'the control ofiice and the field stations for the transmission of controls to govcm the trafiic controlling devices at the field stations, and forthe transmission of indications to give indications in the control office of the condition of the operated devices and the location of trains.

and inwhich selective communication between the control oflice and a particular field station is established by the transmission of suitable codes.

NT QFFICE of the wiring connections to sources which have central or intermediate taps I These features of transmission have been disclosed in various types of systems, such for example as'shown in the application of N. D. Preston et a1., Ser. No. 455,304, filed May 24, 1930. Thus, it is considered sufiicient for an understanding of the present invention, to lustrate how controls, for example, may be transmitted over a line circuit.'

With reference to the accompanying drawing,

' a control ofiice has been illustrated as connected with two outlying field stations by a line circuit including a control line wire 10 and a common return line 12. complete what is termed a control line circuit including a three position'polarized biased-to-neutral line relay F at the control office and ateach of the outlying field stations.

These line wires are employed to:

merely il- In the control ofiice,.a control battery'CB is provided to energize the control line circuit with impulses, the polarities of which are selected by ing between these impulses of selected polarity is actor of the impulses trol line circuit may tangles including measured by an impulsing relay E in combination with a stepping relay bank which is responsive to the impulses applied to the line circuit. This steppingrelay bank includes stepping relays 1V, 2V, 3V and 4V together with :a half step relay VP.

The control of the stepping relay bank is accomplished by a neutral line repeating relay FP, which is energized each time theline relay F is energized, irrespective of the particular polarity of such energization, together with :a :slow acting relay SA which is picked up at the beginning of a cycle of operation and is dropped at the end .of such ,cycle of operation. A relay SAP is a repeater of the relay SA.

A starting button BB is provided for actuating astarting relay C,.which stores the momenta'ry' actuation of the starting button SB .and causes the system to be initiated into a .cycle of operation. .As representative of ,how the chartransmitted over the conbe selected in accordance with the position of code jumpers and control levers, a single control lever L has been illustrated as determining the character of the first impulse of a series, the remaining impulses being determined in accordance with the position of other suitable-controlling contacts.

. An inverse slow acting relay ISA is employed in combination with theslow acting relay SA for to normal conditions irwhich the operation is interrupted.

Although the .control office has been illustrated in a rather specific manner and the field stations have been merely indicated by dotted recthree position ,polar line .relays, it ;is tobe understood that suitable selectin apparatus is associated with the three position polarized vlinerelays at each of the field stations, .allrof which will be well understood by those skilled in the .art.

, Thecontrol oflice and field stations include various sources oi current supply, indicator lamps or the like, bus wiresandsuch'other devices and circuit connections as maybe required for the proper functioning of such a communication system.

It .is believed that .iurther description of the present invention will be .best set ,iorth by the description of various characteristic or typical operations of thesystem.

Operation The system of the present invention is normally in a condition of rest, .but maybe initiated into a cycle of operation from the control oihce whenever thereare controls ready to be transmitted. When a cycle of operation is initiated ,ior the transmission of controls, .a plurality or" distin'ctive impulses are laced upon the control line circuit to accomplish the steP-bY-step ,operation at the control office and at I stations to select the desired station and to trans- ".mit the controlsof that selected station.

The applicationof-aplurality-of impulses to the control line circuit, irrespective of their character, tocomprise .a cycle rof operation causes the .step-by-step operations .of the stepping relay banks. In the control oflice, the operation of the stepping relay bank is associated with the impulsing relay E in such a manner .as to cause the impulses to be applied to the control line circuit eiiective, all of such energization the several I at time spaced intervals in accordance with the actual response of the system. f- Insofar as the embodiment of the present invention is concerned, the circuits are normally de-energized.

Initiation of the system.-The system may be initiated by the actuation of the starting button SB following of course the proper positioning of the control levers in accordance with the controls desired to be transmitted to a selected field station. Although only has been illustrated, and although the lever L is illustrated as controlling the character of the first impulse, it is to be understood that there is a group of code jumpers and control levers for each field station and a startingbutton S3 for each of these groups with a code determining bank oi relays provided, so that only one group of code jumpers and control levers is effective to .govern the character of the impulses of any one cycle of operation. Also thestarting buttons are so arranged with storing relays in combination with the code determining relays, that irrespective of the number of starting buttons whichare actuated at any one time or in rapid succession, only one particular group of levers is rendered whichhas been disclosed for example in the above mentioned application of Preston'et al., Ser. No. 455,304.

However, as typical of all such starting operations,.it is considered sufficient for an understanding of the present invention to know that the actuation of .a starting button SB results in the energization of the starting relay C. Although of the relay C may be accomplished indirectly through the ,mediumpof the code determining means and interlocked bank of relays (above mentioned, but not shown), it is considered suliicient to disclose the present invention to illustrate the relay .C as energized through a pick-up circuit closed directly by the starting button SB.

This pick-up circuit for relay C is closed upon the actuation of the starting button SB from through ,a circuit including the back point of the starting button'SB, windings of the relay C, to As soon as the contacts of the relay C respond to its energization, a stick circuit is closed from throughla circuit including back contact of relay'SAP, front contact 16 of relay C, windings of relay Cto The picking up of the contacts of the relay .6 closes a pick-up circuit for the inverse slow acting relay ISA from through acircuit including back contact 6 of slow acting relay SA, front contact 7 of starting relay C, windings of slow acting relay ISA,'to

With the starting relay C already picked up with its front contact l8v closed, a circuit for the polarity determining relay D is completed at front contact '19 as soon as the inverse slow acting relay ,ISA responds to its energization; while the particular polarity with which the relay D is energized is dependent upon the code jumpers and control-contacts selected by the stepping relay bank. It is to be understood, of ..course, that only one group of code jumpers and control leversrnay be efiective for anyone cycle of operation.

Polarity selection of impulses Assuming for the time being that the impulsing of the line circuits'results in the stepbystep operation of the stepping relay bank, the operation of which will be explained later, we may a. single starting button SB consider the selection selected through the stepping up; and is connected to ofi by the stepping relay bank,

"1,995,272 of the polarities of the various impulses "of the cycle.

Upon the closure of front contacts 18 and-19 of relays C and ISA respectively, the relay D is successively connected to a series of terminals relay bank, including relays 1V, 2V, 3V and iV, in such a way that the relay D is connected to terminal 1 before the first stepis taken; is connected to terminal 2 picked up; is

when the first stepping relay 1V is connected with terminal 3 when the second stepping relay 2V is picked up; is connected to terminal 4 when the third stepping relay 3V is picked the terminal 5 when the stepping relay 4V is picked up.

In actual practice, those particular code jumpers and control levers which are selected by the code determining means, are connected to "these terminals 1, 2, 3, 4 and 5 in such a way that positive or negative potentials will be applied to the relay D dependent upon the particular position of the code jumper or the control lever selected by the stepping relay bank.

Representative of such control, the control leas connected to the terminal 1, so that immediately upon the closure of front contact 19 of relay ISA, the relay D is energized with a polarity dependent upon the position of this lever L.

For example, with the lever L in a left-hand position, a circuit is closed from (B through a and at each of the field stations. i

After the energization of the line circuit for relay D is shifted to the succeeding terminals 3, 4 and 5 during the de-energized condition of'the line circuit, so as to prepare the relay D prior to the closure of the line circuit.

Impulsing and step-by-step operation Each impulse applied to the line circuit repeated by the three position biased to neutral spending step of the cycle. V However, irrespective of the particular polarities of the impulses of 'a cycle, the system is soariortheslow acting I to maintain its contacts in picked up positions circuit including lever L in a lefthand position,

the stick circuit for the relay C pendent upon the to maintain its contacts picked gize the not shown).

For example, the relay FP in the control ofiiee repeats the energized condition of the relay F- With polar contact 23 in either a right-hand or a left hand position.

somewhat longer than the otherneutral relays of the system (for example, relay pick up time is relatively short compared to its drop-away time. This prolongeddrop-away time relay SA is sufliciently long the relay FP closes front conbetween its successive energizations during a cycle I,

of operation.

16 of relay C, windings In other words, when the "relays SA and SAP are picked up sucrelay C is mainrelays SAand SAR are de-energized successively in that order, is momentarily plained.

, The opening f causes the inverse slow acting relay ISA to'loe dethrough a "circuit:

The inverse slow acting relay ISA has slow acting characteristics similar to the relay SA, that is, it is slow in picking up while its drop away period is relatively longer than its pick-up period. This lengthened drop away period is sufficientlylong successive de-energizations of the line circuits time spaced impulses throughout a cycle of operation. These impulses are repeated so as to enerslow acting rel'aySA' periodically, while the de -energized condition between pulses, as caused by the re'layE, periodically energizes the relay ISA. Thus, the relaySA, which back: contact 6 of slow acting relay SA at the beginning of a cycleof operation operation of the relay. E for up between the v is repeated by the relays F and'FP,

circuit from front contact 1'7 'SAP, but as soon as the relay front contact 25 of pick-up circuit to its stick circuit,

contact 28 of relay 1V, windings of break type.

gized and return the system to-normal; .while if an impulse in a cycle of operation fails to be removed,

the relay ISA is de-energized and returns the system tonormal. These functions'ofjthe relays SA and ISA will be more readily apparent as the further operation of the system is set forth.

At'the beginning of the cycle of operation, after -the SA relay is picked up upon the application of the first impulse, the VP relay is energized by a throughfa circuit including of relay SA, front contact 2'7 of relay FP, back contact 28 of relay 1V, windings of relay VP, to

The picking up of the contacts of the relayVP occurs during the pick-up period of the relay SAP has responded to the closure of front contact 14 of relay SA an energizing circuit is completed for the impulsing relay E from through a circuit including front contact 15 of relay SAP, front contact 29 of relay VP, back contact 30 of relay 1V, upper winding of the relay E, to The picking up of the relay E opens the control line circuit marking the end of the first impulse. Also, the closure of the relay E energizes the inverse slow acting relay ISA, as previously mentioned.

The de-energization of .the control line circuit but the relay SA is sufiiciently slow acting to maintain its contacts in picked up positions between successive energizations of the control line circuit, as repeated by the relay FP.

With the controlline de-energized, the half step relay VP is maintained energized through a stick circuit from through a circuit including front contact 1'7 of relay SA, back contact 2'7 of relay FP, front contact 31 of relay VP, windings of relay VP, to

While the contact 2'7 if relay FP is changing from a front point to a back point thereby transferring the energization of a relayVP from its the relay VP is energized by another stick circuit closed from through a circuit including front contact 17 of relay SA, front contact 32; of relay VP, back relay VP, to This is possible in as much as the relay 1V does not pick up until the relay FP is deenergized and the stick circuit of relay VP including front contact 31 has already been closed. In other words, the stick circuit of relay VP including its front contact 32 allows contact 2'7 to be a regular contact instead of the make-before- Also, upon the de-energization following the first impulse, the first stepping relay 1V is energized by a chat closed from through a circuit including front contact 1'7 ,of relay SA, back contact 33 of relay FP, front contact 34 of relay VP, back contact 35 of relay 2V, windings of relay 1V, to As soon as the contacts of the relay 1V are picked up, a stick circuit is closed from through a circuit including front contact 17 of relay SA, front contact 36 of relay 1V, windings of relay 1V,

control desired to of relaylV, windings of relay 2V, to

polarity, as

stepping relays and half The picking up of the relay 1V opens the energizing circuit for the relayE at back contact 30 and. at the same time connects the relay D to the terminal 2, wihch has positive or negative energy applied thereto depending upon the the closure ofback contact 22 of relay E, the second impulse of selected polarity is applied to the line circuit. The repeating ofthis impulse hy the relay FP opens its back contact 2'7 and drops the relay VP, as there can be no pick-up circuit closed with only the first stepping relay 1V picked up. r

The deenergization of the relay VP closes an energizing circuit for the relay E from through a circuit including front contact 15 of relay SAP, back contact 29 of relay VP, back contact 3'7 of stepping relay 2V, front contact 38 of stepping relay 1V, lower winding of relay E, to

The relay E again picks up its contacts opening the line circuit, and simultaneously energizing the inverse slow-acting relay ISA through front contact 25.

The deenergization of the control line circuit following the application of the second impulse, energizing the second stepping relay 2V by a circuit closed from through a circuit including front contact 1'7 of relay SA, back contact 33of relay FP, back contact 3A of relay VP, backcontact 39 of relay 3V, front contact 40 The picking upof the contacts of the relay 2V closes a stick circuit from through a circuit including front contact 17 of relay SA, front contact 41 of relay 2V, winding of relay 2V, to

The picking up of the relay 2V opens the energizing circuit for the relay E again causing the control line to be energized with a selected previously explained.

Similar step-by step impulsing of the control line circuit with selected polarities continues throughout the cycle of operation until the fourth stepping relay is picked up and the fifth impulse has been applied to the control line circuit, when the relay E is energized by a circuit closed from through a circuit including front contact 15 of relay SAP, front contact 29 of relay VP, front contact 42 of relay 4V, upper windings of relay E, to

This energization of the relay E opens the line circuit, but as the relay 4V is the last stepping relay, the relayE continues to be energized which prolongs the deenergized condition of the line until the'relay SA drops. The dropping of the relay SA opens thestick circuits of the step relay VP at front contact 1'7, as well as the stick circuit for the relay C at front contact 8. Thus, the relay C and the stepping relays assume deenergized positions at substantially the same time, but as the relay SAP is somewhat slow in releasing the relay E is not deenergized until the stepping relays and the half stop relay VP have dropped simultaneously.

Thus, the relay D has plenty of time, as it is quick acting, to assume its biased to neutral position in response to the opening of front contact 18, while the relay E is dropping away and before the back contact 22 of relay E closes.

The system is thus restored to normal until the starting relay C is again energized in response to a starting button.

From the above description, it will be readily apparent that the stepping relay bank ismade be transmitted. Thus, upon 4 ping of the relay SA upon the continued deenerfrom the spirit or scope of the present invention gization of the control line circuit causes the except as limited'by the appended claims. stepping relay bank to be deenergized, and pre- What I claim is: v Vents the operatifln 0f the a p relay VP 1. In acentralized traific controlling system for and impulsing relay E, and thereby restores the railroads, a'line circuit, a polarity determining de-energization of the control line circuit efiects circuit for operating aid impulsing relay, 2. slow the de-energization of the slow acting relay SA, acting relay? periodically energlzed by said m;

synchronized condition.

In other words, irrespective of Whether a cycl v dropped at theend of said series, an inverse slow of operation ceases to continue during-the appht g relay periodically energiznd by rest conditions. r said impulsing relay, a second means including A1 I can be SBQII $11131? upon each energlza'tlon said polarity determining relay for governing said of the control line c1rcu1t,the contacts of the relay inverse 1 acting relay, and means responsive m new positions and upon each to said first and said second means for preventenergization of the control line circuit the stepm t impulsing of a line circuit ping relay ban-k takes one Step- In other Words: 2. In combination; a line circuit; a repeating the c ro Contact 34 of the relay causes relay for repeating the condition of said line cirthe buses 50 and 60 to be alternately energized Quit; 'means includmg an jmpulsing relay for last relays for each bank). Such an arrangement has the advantage that a long chain of contacts is not included in the various pick-up circuits thereby increasing the resistance of the circuits and reducing their reliability.- I

It will be noted that a similar arrangement is provided for the control of the relay E and the circuitcontrol of the relay VP, namely, that the fronts gizing circuit jncludi line repeating relay; a second slow acting relay having an energizing circuit including its own acting relay and a, front contact of said impulsing relay; a step-by-step means having energizyandabackcontactofsaid line reevery stepping relay of the bank included in each said impulsing relay to of the circuits.

A communication system has thus been described which is capable of resynchronization irrespective of Where the operation fails to continue. Also, variouscircuit improvements for open said line circuit after each step; and starting means effective to start Having described a centralized trafiic control Sy One embodiment of the present "a predetermined rate determined by the timing characteristics of said first and second slowacting relays.

mg circuits including a front contact of said first peating relay, said step-by-step means controlling FREDERICK w; BRIXNER, I 

